1. SCOPE OF INVENTION
This invention relates generally to preventing fuel oil and sea water in a single container or tank from becoming colloidalized or physically emulsified with one another, and more particularly to such preventive measures within a diesel fuel oil/sea water ballast tank of a ship.
2. PRIOR ART
It is well known on ocean going vessels and ships to pump sea water into the ship's fuel oil tanks as the fuel oil is depleted from the tanks. The sea water is used as a ballast to maintain desired keel depth which, in turn, provides optimal operation of the ocean going vessel or ship.
Although this ballast maintenance technique is quite desirable, i.e. the replacement of fuel oil as used with sea water, this practice has presented vessel operators with certain problems which, heretofore, have remained unsolved. The motion of the ship at sea, as well as algae and proteins which are found in sea water, act to create a colloidal condition or suspension of oil droplets suspended in the sea water itself, and/or visa versa. Furthermore, during violent storms, the sea water can actually be caused to become suspended within the fuel oil.
When the fuel oil has been fully spent from each tank, it has been the practice to pump the sea water ballast back into the ocean before refilling the fuel tanks with fresh fuel oil. If oil droplets are found suspended in the discharged sea water, the purging of the tank results in a loss of emulsified or colloidalized fuel oil and also represents a serious environmental pollution problem.
Should sea water become suspended in the fuel oil to any substantial degree, the actual ship power plant may fail or become corroded. Such an occurrence often proves to be a dangerous condition in open seas.
The use of hollow fibers in conjunction with the absorption, transfer or displacement of liquids is well known. The following U.S. Patents are directed to the use of such hollow fibers:
______________________________________ U.S. Pat. No. 4,805,343 Patterson, et al. U.S. Pat. No. 5,303,503 Patterson U.S. Pat. No. 5,177,897 Patterson U.S. Pat. No. 4,928,427 Patterson U.S. Pat. No. 4,860,577 Patterson ______________________________________
Applicant is also aware of a number of prior art U.S. patents which are related to the breaking down of existing emulsification or colloidal suspension of oil and water as follows:
______________________________________ U.S. Pat. No. 3,179,603 Edwards, et al. U.S. Pat. No. 3,729,410 Abadie, et al. U.S. Pat. No. 3,800,944 Yost U.S. Pat. No. 3,902,996 Murkes U.S. Pat. No. 4,297,220 Meitzner, et al. ______________________________________
However, this group of prior art references merely deals with the rectification of an undesirable situation, that being the preexistence of the emulsification or colloid mixture of the oil and water, whereas the present invention deals with preventing its formation in the first instance.